2015 Chevrolet Tahoe fuel system problems

We have been noticing an excessive fresh fuel smell which we believe to be coming from the exhaust when we start our vehicle to warm up prior to driving in the morning. Also sounds like exhaust is missing a little at idle. Took it in and dealer could not find any codes relating to our problem. They did however find a TSB 14858 for possible high pressure pump leak. They replaced high pressure fuel pump and seals with new line and test drove vehicle. They state vehicle is ok.

I had a system failure light that came on my 2015 tahoe. When I brought it to voss chevrolet dealership in centerville ohio, they told me that my high pressure fuel pump was failing and that I would need to replace it along with the fuel lines. Upon further research I learned that GM had issued a recall bulletin (TSB 14858) in 2015 for select 2015 tahoes. The tahoe's affected included vehicles with an 8 cylinder engine (rpo l83 or l86).